Cylinder lock with annular grooves



March 17, i931. J. cRoNlNG CYLINDER LOCK WITH ANNULAR GROOVES Filed June 3 1925 ATTORN EY5 Patented Mar. 17, 1931 UNITED STATES PATENT OFFICE JOHANNES CRONING, OF HAMBURG, GERMANY, ASSIGNOR, :BY` MESNE-ASSIGNMENTS,

` T0 CROWN LOCK COMPANY, A CORPORATION lOIE' `(YLIINIDIER LOCK WITH ANNULAR GROOVES I Application led l.Tune 3, 1925, Serial No. 34,649, and in Germany September 22, 1924.

The present invention relates to a cylinder lock wherein the moving parts'are adapted to be secured against unauthorized use.

Cylinder locks commonly comprise a cylinder (herein called the locking cylinder) carrying pin tumblers, the ends of which are projected beyond the circumferenceof the cylinder by springs, except when the proper key moves them against the force of the springs, so that their ends correspond with the circumference of the cylinder, permitting it to be turned within the hollow (herein called the lock cylinder) which carries it. In the conventional standard cylinder lock structure, the pin tumblers are in two parts, one part carried by the locking cylinder with the keyway beneath and communicating with it, and the other carried by the surrounding cylinder, or lock cylinder, with the spring above it. In all cylinder locks, so far as known, holes to receive the pins, or a portion thereof, have been provided in the surrounding cylinder. It is an object of the present invention to reduce the cost of cylinder locks by eliminating the diiculties and expenses connected with the manufacture and assembly of locks having h'oles in the hollow cylinder receiving or containing the pins or a part thereof. As it is very tedious and inconvenient, especially in winter with cold hands, when inserting the locking cylinder, to manipulate this until the locking pins and holes are opposite one another and as on the other hand the production of the holes is very diiiicult, according to the present invention the locking pins are received in annular grooves or recesses in the surrounding cylinder so that the vkey can be withdrawn from the inserted locking cylinder in any position thereof. r

An example of construction according to the invention is illustrated in the drawings.

Fig. 1 is a sectional view through the lock assembly including the lock and locking cylinders;

Fig. 2 is an enlarged elevational view of the locking cylinder with a key inserted. therein, the tumblers being shown 1n re-` tracted position;

l Fig. 3 yis a view similar to Fig.` 2, with the tumblers projected and the key removed; and Fig. 4 is a transverse sectional view on the line le-4C of Fig. 2. y When the proper key isinserted in the locking cylinder, the ends of the pins correspond with the circumference of that cylinder, so that the locking cylinder a can be Withdrawn from the lock cylinder b, withdrawing the projection c from the shaft and thus unlocking it. The preferred form of locking cylinder shown in the drawings'comprises onepiece pins f provided with an oi'set portion g, so mounted in the cylinder that the oifset portion is engaged on one side by a spring s tending to force the end of the pin beyond the circumferencaof the cylinder, and said offset portion may be engaged on the other side by a key c inserted in the keyway of the cylinder and the pin thus moved to a position where the end corresponds with the circumference of the cylinder. The locking cylinder a is provided with a cylindrical projection c for locking a shaft or the like and is guided in a lock cylinder casing b. rlhe locking pins e engage with annular grooves d. The lock cylinder b can be screwed or otherwise secured in the casing or the like of the part to be locked or may even form a part of this casing.

The cylinder lock thus constructed with annular recesses in the cylinder or casing surrounding the lock cylinder to receive the ends of the pins when the withdrawalfof the key permits the springs to force the ends of the pins beyond the circumference of the cylinder into the annular recesses, is substanf tially as secure as the cylinder lock wherein the pins extend from holes in both members, and more advantageous for many purposes, because easier to make and assemble and better adapted'to accomplish simply and eiliciently the locking of sundry parts Where the provision of holes to receive the projecting ends of the pins is very diiicult.

Having thus described my invention, what I claim is 1. In combination with a removable lock cylinder provided with means for retaining tumblers assembled therein so that said tumblers are projectable beyond the circumferibo ence of the c linder and withdrawable therewithin by t e proper key but inseparable from the cylinder, a hollow member surrounding said cylinder having annular recesses positioned to receive the projected ends of the tumblers.

2. A locking device comprising a removable locking cylinder containing pin-tumblers, springs to move said tumblers so that the ends project beyond the circumference of the cylinder, means preventing the separation of said tumblers from the cylinder and a keyway communicating with the tumblers to receive a key to move them wholly within the circumference of the cylinder and a hollow member adapted to receive said cylinder and vprovided with annular recesses to receive projecting ends of the pin-tumblers.

3. A cylinder lock comprising a casing provided with a cylindrical hollow bore having annular recesses therein, a removable lock cylinder mounted in the bore, said cylinder being provided with apertures and a key- Way, tumblers mounted in said apertures, means for preventing the separation of the `tumblers from the cylinder When it is removed from the bore, and springs carried by the cylinder for acting on the tumblers to project the ends thereof beyond the circumference of the cylinder and into the recesses in the casing, said tumblers being movable by a key inserted in the keyway in said cylinder so that the ends of the tumblers are Withdrawn from the recesses and Within the circumference of the cylinder.

In testimony whereof I have affixed my signature.

JOHANNES CRONING. 

